More and more people (adults and children) wear awareness bracelets (wristbands), necklaces, etc. These awareness items can display one's allegiance to a company, a cause, a charity, a business, a sports team, an individual, a character, a movie, a product or service, a destination, etc. Essentially, the awareness item can display an allegiance to just about anything.
Specifically, awareness items can promote brand awareness for businesses, which can result in higher sales of not only one product, but on other products associated with that brand. A brand can take many forms, including a name, product/service, logo, symbol, slogan, color, etc.
Awareness items can also promote awareness to a cause typically referred to as a concept brand. One of the most notable concept brands is breast cancer awareness, which uses a pink ribbon as a symbol to raise awareness of breast cancer and educate people about its symptoms and treatment options.